New frequencies and geometries for plasmonics and metamaterials

The manipulation of light at the nanoscale has become a fascinating research field called nanophotonics. It brings together a wide range of topics such as semiconductor quantum dots or molecular optoelectronics and the study of metal optics, or plasmonics, on one hand and the development of finely designed structures with specifically engineered optical properties called metamaterials on the other. As is often the case, it is at the boundary of these two domains that most novel effects can be observed. Plasmonics has for instance enabled the detection of single molecules due to the large field enhancement which exists in the vicinity of nanostructured metals. Thanks to the confinement of electromagnetic waves below the diffraction limit plasmonic systems are also foreseen as ideal conduits connecting electronic and photonic systems. On another hand, when a material is patterned on a scale smaller than the wavelength, its optical properties are reflections of the structure of the patterned material rather than the material itself, a concept known as metamaterial. This has allowed researchers to obtain exotic optical properties such as negative refractive indices and can be implemented in devices acting like invisibility cloaks or perfect lenses. While the prospects for nanophotonics are far-reaching, real-life applications are severely limited by the intrinsic absorption of metals and the current fabrication methods mostly based on electron-beam lithography which is slow and costly. In this thesis, we investigate these issues by considering the potentials of other polaritonic materials such as semiconductors, silicon carbide and graphene for field confinement applications. This is achieved through the combination of both numerical studies and sample fabrication and testing with the help of international collaborators. Our results show much improvement over the metallic structures typically used, with an operating range covering the near- and mid-infrared as well as the terahertz. The field compression can also be much greater compared to conventional plasmonic materials, with near-field enhancements reaching four orders of magnitude. Furthermore, we analyse theoretically the optical properties of metallic gyroids which are obtained by self-assembly - a promising chemical route for fabricating large-scale 3D structures with molecular sized resolution. These materials exhibit unexpected properties such as negative refraction and could in consequence be used as thin lenses or wave-plates. Last, we develop and apply a theoretical formulation of Fano theory for the case of plasmonics. It allows a clear and simple physical understanding of the interference spectra which are commonly encountered in nanooptics.Open Acces

Commentary to “Lobbying for Endorsement of Community Psychology in Australia”

The struggle to have community psychology endorsed as one of the recognized psychological specialization among the health professions could not happen in Italy in quite the same form, since in our country the most prestigious professions (doctors, lawyers, architects, engineers etc.) are regulated through “professional orders” , which are instituted through specific laws passed in Parliament. University graduates aspiring to practice one of these “legalized” professions must pass a special examination (similar to the bar exam for lawyers in the United States) to become members of the professional order. Different professions can create scientific or professional associations, which have less prestige and power than professional orders. In fact, many requests by professional associations to become an order often remain in the form of proposed laws for years in the Italian parliament. In Italy, a big battle, which required most of the same lobbying described by our Australian colleagues, actually took place in the seventies and eighties to obtain the passage of this kind of law

Commentary to “Lobbying for Endorsement of Community Psychology in Australia”

The struggle to have community psychology endorsed as one of the recognized psychological specialization among the health professions could not happen in Italy in quite the same form, since in our country the most prestigious professions (doctors, lawyers, architects, engineers etc.) are regulated through “professional orders” , which are instituted through specific laws passed in Parliament. University graduates aspiring to practice one of these “legalized” professions must pass a special examination (similar to the bar exam for lawyers in the United States) to become members of the professional order. Different professions can create scientific or professional associations, which have less prestige and power than professional orders. In fact, many requests by professional associations to become an order often remain in the form of proposed laws for years in the Italian parliament. In Italy, a big battle, which required most of the same lobbying described by our Australian colleagues, actually took place in the seventies and eighties to obtain the passage of this kind of law

"Daudet, James, and the Revision of the Nineteenth-Century Wifely Adultery Plot"

Although it is widely known that Henry James took inspiration from Alphonse Daudet’s L’Evangéliste (1883) for The Bostonians, and from Numa Roumestan (1881) for “The Liar,” the influence of the French novelist on James’s late fiction is still far from being fully grasped or acknowledged. In this essay I will read Daudet’s La petite paroisse. Moeurs conjugales (1895) together with James’s The Golden Bowl (1904) and discuss the similar ways in which these two works revised the nineteenth-century form of the “wifely adultery novel” (Overton 2002) within their respective literary and cultural contexts. My argument is that they challenged both the social stigmatization attached to the adulteress and what were taken to be ‘natural’ relations between husband and wife, and within the family circle

The International Dimension of "The Death of the Lion"

This essay reconsiders some critically established ‘germs’ for Henry James’s “The Death of the Lion” (1894), traced back to the 1893 demise of Guy de Maupassant and to the latter’s only visit to England in the summer of 1886. On this latter occasion, Maupassant was ‘chaperoned’ by his American friend Blanche Roosevelt, a well-known literary journalist in the London and Paris circles. The unexplored connection with Roosevelt invites a new reading which gives prominence to the American woman character in the tale (Fanny Hurter) and unveils an international subtheme within. In light of such a reading, as well as of authoritative studies which have analyzed “The Death of the Lion” against the rise of modern literary journalism, I will also re-examine the role of the first-person narrator, an unnamed ‘repented’ literary journalist, in thwarting the possible relation between Neil Paraday and his American admirer

Management of exercise-induced glycaemic imbalances in type 1 diabetes

Regular moderate-intensity exercise is strongly recommended for its beneficial effects in all people. In patients with type 1 diabetes, however, the exercise-associated glycemic imbalances remain an unresolved clinical challenge. Current guidelines require an in-depth understanding of the glycemic responses to exercise and each patient has to discover, by trial-and-error, his/her own strategy, several attempts being usually required to gain sufficient experience. Consequently, fear of hypoglycemia remains the strongest barrier to physical activity. This paper explores the potential strategies that may be employed to minimize the risk of exercise related glycemic imbalances. Moreover, a newly developed algorithm (ECRES, Exercise Carbohydrate Requirement Estimating Software) is described, which estimates on a patient-and situation-specific basis the glucose supplement required by the patient to maintain safe blood glucose levels. The algorithm was tested on 27 patients who performed three 1-hr constant intensity walks (each starting at a different time interval following insulin injection). Results showed that in 70.4% of the trials, independent of the time of day, the algorithm provided a satisfactory estimate of the carbohydrates needed by patients to complete the exercise with a glucose level within safe thresholds (i.e. 3.9 - 10 mmol\ub7L -1). Despite the algorithm requires further experimental testing to be applied by the majority of patients, these results indicate its potential usefulness as a tool for preventing immediate exercise-induced glycemic imbalances (i.e. during exercise) in type 1 diabetic patients, in particular for spontaneous activities not planned in advance, thus allowing all insulin-dependent patients to safely enjoy the benefits of exercise

How Italian Female Local and National Politicians Perceive and Cope with Obstacles in a Gatekeeping Political Culture

In spite of decades of women’s political battles, there is a persistent underrepresentation of women in legislative bodies, with only 23.8% in 2018. In this chapter, we discuss theories and empirical studies that have explored what kind of obstacles female politicians are more likely to meet and how they cope with them, when they face more hurdles, and why we need more women elected to political office. Furthermore, we report the results of several studies, which have involved 233 Italian national politicians (46% females), 425 local politicians (56% females), 626 political activists (44% females), and 3249 ordinary citizens (49% females). Results of these studies show that female politicians face mainly external obstacles as the gatekeeping theory maintains. Women find obstacles all along their political career supporting labyrinth hypotheses. Females at all levels of political involvement scored higher in self-transcendence values that emphasize concern for the welfare of others, partially confirming the politics of presence theory. Female politicians were also more open to change and less conservation oriented than their male colleagues. Our findings in general support ethical struggles for a more balanced gender representation